(1) Field of the Invention
The present invention relates to a terminal cover to be mounted on an insulator so as to protect terminals held by the insulator, wherein the insulators are laminated with each other to constitute a joint connector.
(2) Description of the Related Art
In a motor vehicle as a mobile unit, a wiring harness is arranged to supply electric power from a power source such as a battery and the like to electronic equipment such as various lamps and motors to be mounted. The wiring harness has a plurality of electric wires, a plurality of terminals attached to ends of the electric wires, and connector housings for receiving the terminals therein. The connector housing and a plurality of terminals constitute a connector. In general the wiring harness has a plurality of connectors.
Recently, in response to the increase of the electronic equipments mounted on the motor vehicle, the wiring harness has been once constituted as a plurality of subhamesses, each of which is for a corresponding function of the electronic equipment, then obtained by assembling these subharnesses. Therefore, the connection of each electric wire among subharnesses becomes complicated, causing a deterioration in the workability during the assembly of the wiring harness and an insecure quality thereof when things come to the worst.
A joint connector 5 as shown in FIG. 22, by which the connection among electric wires can be easily carried out, has been proposed. A plurality of housings 40 as insulators shown in FIG. 17, on each of which pressure-welded terminals 30 shown in FIG. 14 for use in a joint connector 5 are mounted, are laminated with each other so as to obtain the joint connector 5 shown in FIG. 22.
The joint connector is defined as a connector, in which a plurality of terminals received in respective connector housings are electrically connected with each other in accordance with a predetermined pattern. In this case, the housings 40 to be laminated with each other corresponds to an aforementioned connector housing.
The pressure-welded terminal 30 is prepared, for example, by bending an electrically conductive sheet metal. As shown in FIGS. 14 and 15, the pressure-welded terminal 30 has a flat base 35a on which an electric wire 4 shown in figures such as FIG. 20 are placed, a pair of sidewalls 35b, a wire-connecting part 31, and an electric contacting part 32.
The base 35a is formed in a band plate-shape. Each of a pair of the sidewalls 35b is also formed in a band plate-shape. Each of a pair of the sidewalls 35b continues to a corresponding periphery of the base 35a. Each of a pair of the sidewalls 35b perpendicularly rise from the corresponding periphery of the base 35a. 
The wire-connecting part 31 has a pair of bent pieces 33 facing each other and a pressure-welding part 31a. Each bent piece 33 arises perpendicularly with relation to the base 35a. A pair of the bent pieces 33 is bent toward the base 35a so as to hold the wire 4 placed on the base 35a. 
The pressure-welding part 31a has three pairs of press-in blades 34a, 34b and 34c facing each other. The three pairs of press-in blades 34a, 34b and 34c arise perpendicularly with relation to the base 35a and protrude in the direction for accessing to each other from the inner face of the corresponding sidewall 35b. 
The wire 4 is press-fit among the three pairs of press-in blades 34a, 34b and 34c so that the blades cut deep into a coating of the wire 4 to come into contact with the core of the wire 4, thereby the electric connection between the blades and the wire 4 is ensured, that is, the blades 34a, 34b and 34c are pressure-welded to the wire 4.
The electric contacting part 32 has an open hole 36 (as shown in FIG. 15) opened in the base 35a and a tab 37 as a connecting piece, which can rise from the base 35a. The tab 37 is formed in a band-shape. The tab 37 is formed integrally with the base 35a at an end of the tab 37 and continues to the wire-connecting part 31.
By being bent, the tab 37 can be set in either a state in which the tab 37 rises perpendicularly to the base 35a or a state in which the tab 37 is set parallel with the base 35a as shown in FIG. 14 by an alternate long and two short dashes line. Once the tab 37 is bent so as to rise perpendicularly to the base 35a, the tab 37 keeps this position, while when the tab 37 is set parallel with the base 35a, then the tab 37 keeps such a position.
The state in which the tab 37 rises perpendicularly to the base 35a corresponds to a state of electric connection, while the state in which the tab 37 is set parallel to the base 35a corresponds to a state of electric insulation. When one housing 40 in which the pressure-welded terminals 30 (for use in the joint connector 5) are held is laminated to another housing, the tab 37 in the electric connection state extends toward a pressure-welded terminal 30 held in the other housing. Moreover, the tab 37 in the electric connection state can be electrically connected to a pressure-welded terminal 30 held in the other housing. As shown in FIG. 15, the open hole 36 is provided with a contacting spring piece 36a to pressure-weld an end of the base 35a to the tab 37 of the other pressure-welded terminal.
The pressure-welded terminals 30 described above are laminated such that the bases 35a are set parallel with each other having a space therebetween. The tab 37 of one pressure-welded terminal situated below in FIG. 15 is inserted into the open hole 36 of the other pressure-welded terminal situated above in FIG. 15, thereby the electric contacting part 32 electrically connects the pressure-welded terminals, laminated with each other, to each other.
At this time, the tab 37 of the one pressure-welded terminal 30 situated below is nipped by the end of the base 35a and the contacting spring piece 36a of the other pressure-welded terminal 30 situated above.
Each pressure-welded terminal 30 is press-fit in a corresponding groove 41 for receiving a terminal in the housing 40, thereby each pressure-welded terminal 30 is received in and held by the housing 40.
Upon the press-fitting of the pressure-welded terminal 30 into the groove 41, when the pressure-welded terminals 30 adjacent to each other are to be electrically connected, a connecting member 39 that connects ends of the base 35a near to the wire-connecting part 31 to each other is left without being removed from the base 35a as shown in FIG. 16. When the pressure-welded terminals 30 adjacent to each other are kept being electrically insulated, the connecting member 39 is removed from the base 35a. 
The housing 40 is made of electrically insulating synthetic resin and has a rectangular plate body 42 and a plurality of grooves 41 for receiving a terminal as shown in FIGS. 17-22. The plate body 42 has a bottom wall 42a, a pair of sidewalls 42b, and a plurality of partition walls 43, each of which rises perpendicularly from the bottom wall 42a. 
The bottom wall 42a is formed flat and rectangular in its plane shape. The sidewalls 42b are arranged in parallel facing each other. Each sidewall 42b is formed continuously from the corresponding periphery of the bottom wall 42a. Each sidewall 42b rises perpendicularly to the bottom wall 42a, that is, each sidewall 42b arises perpendicularly from the corresponding periphery of the bottom wall 42a. 
Each sidewall 42b is provided with a guide projection 42c. The guide projection 42c protrudes in the direction for leaving from the bottom wall 42a from an end of the sidewall 42b, which is distant from the bottom wall 42a. That is, the guide projection 42c rises perpendicularly from the corresponding periphery of the bottom wall 42a. 
Each guide projection 42c is formed in a blade-shape along the sidewall 42b. When the housings 40 are laminated with each other, the guide projection 42c guides the housing 40 in such a manner that a locking claw 44 (explained later on) of one housing 40 and a corresponding claw receiver 45 (explained later on) of another housing 40 are engaged with each other.
The partition walls 43 are arranged in parallel with each other having a space therebetween. The partition walls 43 are arranged in parallel with a pair of the sidewalls 42b between a pair of the sidewalls 42b. 
The groove 41 for receiving the pressure-welded terminal 30 is surrounded by the partition walls 43 adjoining each other and the bottom wall 42a. A plurality of grooves 41 are formed. As shown in FIG. 18, the pressure-welded terminal 30 is placed on one surface 47a of the bottom wall 42a. On the other hand, the pressure-welded terminal 30 is not placed on another surface 47b of the bottom wall 42a, which is situated at the back of the surface 47a. 
Each sidewall 42b is provided with a hollow groove 48a and a through hole 48b. Each hollow groove 48a extends along the groove 41 and is formed so as to become hollow from a surface of the corresponding sidewall 42b, which is located outside the housing 40. The through hole 48b runs along the direction from the one surface 47a to the other surface 47b in the sidewall 42b. The through hole 48b is formed in a rectangular shape in its plan view.
As shown in FIG. 19, in the housing 40, each pressure-welded terminal 30 is inserted into the groove 41, which is selected as desired out of a plurality of the grooves 41. The pressure-welded terminal 30 is inserted into the groove 41 from an end of the groove 41 as shown in FIG. 18.
The housings 40, in each of which the terminal 30 is inserted, is laminated with each other in such a manner that the plate bodies 42 are laminated parallel with each other having a space therebetween, thereby constructing the connector (joint connector) 5 as shown in FIG. 22.
At this time, as shown in FIG. 20, the wire 4 is pressure-welded to the terminal 30, which is received in and held by the housing 40. Then, as shown in FIG. 21, the housings 40, in each of which the wire 40 is mounted, are laminated with each other. Further, the terminals 30 are electrically connected to each other when the corresponding housings 40 are laminated adjacently with each other and the corresponding tab 37 is set in the electric connection state, and the terminals 30 adjacently situated are electrically connected to each other when the connecting member 39 is left without being removed.
When the housings 40 are laminated with each other to construct the joint connector 5, a cover housing 49 is laminated atop thereof as shown in FIG. 21. Since the cover housing 49 has a similar structure to that of the housing 40, the same reference numerals are used for the same elements thereof. The cover housing 49 is not provided with the partition wall 43, therefore no groove 41 for receiving a terminal is formed therein.
Although FIGS. 19-22 are illustrated in such a manner that a terminal 30 is received into every groove 41, the housing 40 does not necessarily receive a terminal 30 into every groove 41 thereof. That is, in the housing 40, a pressure-welded terminal 30 is inserted into only the groove 41, which is selected as desired from a plurality of the grooves 41.
The housing 40 is provided with a plurality of holes (not shown in the figure), which do not disturb the tab 37 of the terminal 30 situated below from entering into the open hole 36 of the terminal 30 situated above.
Furthermore, the housing 40 and the cover housing 49 have a plurality of the locking claws 44 and the claw receivers 45, by which these housings fix to each other upon the lamination thereof. As shown in FIG. 17B, the locking claw 44 protrudes from the other surface 47b on which the terminal 30 is not placed. As shown in FIG. 17B, the claw receiver 45 is provided between the sidewall 42b and the partition wall 43, which is situated nearest to the sidewall 42b. The claw receiver 45 of one housing 40 engages with the locking claw 44 of the other housing 40, which is adjacently laminated on the one housing 40.
When the wiring harness is constituted with the housings 40 described above, first the wire 40 is pressure-welded to the terminal 30 mounted in the housing 40, thereby the subharness is constituted. Then, the housings 40 of the subharness are laminated to each other, thereby the joint connector 5 is constructed and the wiring harness is assembled.
Further, in an assembly line for assembling the wiring harness, at least the subharness needs to be conveyed from a pressure-welding step of the wire 4 in the housing 40 to a laminating step of the housings 40. Consequently, there is the possiblity that the tab 37 is deformed by being touched by hands of the workers. If the tab 37 is deformed, the terminals 30 cannot be securely connected to each other, causing a deterioration in the production yield of the wiring harness.
Furthermore, if the tab 37 is deformed, there is the possibility that the tab 37 disturbs the engagement between the locking claw 44 and the claw receiver 45 when the housings 40 are laminated to each other. Therefore, the housings 40 cannot be securely laminated to each other, causing a further deterioration in the production yield of the wiring harness.
It is therefore an objective of the present invention to solve the above problem and to provide a terminal cover for protecting a terminal, which is mounted to the insulator constructing the joint connector by the lamination thereof and held by the insulator, thereby preventing deterioration in the production yield of the wiring harness.
In order to attain the above objective, the present invention provides a terminal cover to be mounted on an insulator, which arranges and holds a plurality of pressure-welded terminals in parallel therein, a plurality of the insulators being mutually laminated to constitute a joint connector. When the terminal is held by the insulator and the insulator being laminated to the other insulator, the terminal having a connecting piece, which extends toward the other terminal mounted in the other insulator and is connectable to the other terminal. The insulator has a wall for placing the terminal thereon and a pair of guide projections perpendicularly arising from a pair of the peripheries of the wall facing each other, and the terminal cover comprising: a cover body to be mounted on the insulator being nipped between a pair of the guide projections; and a protecting projection, which protrudes from an end of the cover body toward the outside and situates the connecting piece between the wall and the protecting projection when the cover body is mounted on the insulator.
According to the construction described above, the connecting piece is situated between the protecting projection and the wall, thereby preventing hands of the workers and so on from touching the connecting piece during the conveyance of the intermediate products from one step to another step of the assembly of the wiring harness. Therefore, the connecting piece is prevented from deforming during the assembly of the wiring harness, thereby a deterioration in the production yield of a wiring harness is prevented.
Preferably, an end of the cover body is provided with a flat protecting surface along the direction in which the connecting piece extends toward the other terminal, the protecting surface comes into contact with the connecting piece when the cover body is mounted on the insulator, and the protecting projection protrudes from the protecting surface toward the outside.
According to the construction described above, the protecting surface is formed along the connecting piece and comes into contact with the connecting piece when the cover body is mounted on the insulator, thereby the protecting surface prevents the connecting piece from deforming during the conveyance of the intermediate products. Further, the protecting projection protrudes from the protecting surface, thereby securely situating the connecting piece between the wall and the protecting projection and more securely preventing hands of the workers and so on from touching the connecting piece during the conveyance of the intermediate products from one step to another step of the assembly of the wiring harness. Therefore, the connecting piece is securely prevented from deforming during the assembly of the wiring harness, thereby a deterioration in the production yield of a wiring harness is securely prevented.
Preferably, the insulator has a claw receiver engaging with a locking claw of the other insulator when the insulators are mutually laminated so as to constitute the joint connector, and the terminal cover has a locking member, which protrudes from the cover body toward the claw receiver and engages with the claw receiver when the cover body is mounted on the insulator.
According to the construction described above, the locking member engages with the claw receiver of the insulator, thereby the cover body is securely prevented from positionally being off in relation to the insulator upon its mounting on the insulator. Therefore, the connecting piece is securely prevented from deforming during the assembly of the wiring harness, and a deterioration in the production yield of a wiring harness is securely prevented.
Preferably, the insulators are mutually laminated so as to constitute the joint connector by using a setting jig having a plurality of holders, which are capable of holding the insulators and separable from each other, the insulator is mounted in the holder by being moved along the wall, and the terminal cover has a pair of lock releasing members for enlarging a space between a pair of the guide projections as the insulator is mounted in the holder when the terminal cover is mounted on the insulator.
According to the construction described above, the lock releasing members gradually enlarge the space between a pair of the guide projections as the insulator is mounted in the holder, thereby the cover body is detached from the insulator in response to the mounting of the insulator. Therefore, the connecting piece is securely prevented from deforming during the assembly of the wiring harness, and a deterioration in the production yield of a wiring harness is securely prevented and the time required for assembling the wiring harness can be reduced.
Preferably, the lock releasing member comprises: a releasing member body, which protrudes from the periphery of the cover body toward the outside, a pair of the peripheries having a space therebetween along the direction crossing at right angles to the mounting direction of the insulator into the holder, and comes into contact with the setting jig when the insulator is mounted in the holder; and an inclined surface, which is provided at an end of the releasing member body near to the guide projection, capable of coming into contact with the guide projection, and gradually inclined toward the inner direction of the cover body as approaching the guide projection.
According to the construction described above, when the insulator is mounted in the holder, the inclined surface securely gradually enlarges the space between a pair of the guide projections, thereby the cover body is securely detached from the insulator in response to the mounting of the insulator. Therefore, the connecting piece is securely prevented from deforming during the assembly of the wiring harness, and a deterioration in the production yield of a wiring harness is securely prevented and the time required for assembling the wiring harness can be reduced.
Preferably, the locking member gradually slips out from the claw receiver along the mounting direction of the insulator as the insulator is mounted into the holder.
According to the construction described above, the cover body is more securely detached from the insulator in response to the mounting of the insulator into the holder. Therefore, the connecting piece is securely prevented from deforming during the assembly of the wiring harness, and a deterioration in the production yield of a wiring harness is securely prevented and the time required for assembling the wiring harness can be reduced.